Pterocarpan

Pterocarpans are derivatives of isoflavonoids found in the family Fabaceae.

It is a group of compounds which can be described as benzo-pyrano-furano-benzenes (i.e. 6H-[1]benzofuro[3,2-c]chromene skeleton) which can be formed by coupling of the B ring to the 4-one position.

[1] 2'-hydroxyisoflavone reductase is the enzyme responsible for the conversion in Cicer arietinum[2] and glyceollin synthase for the production of glyceollins, phytoalexins in soybean.

[3]

Pterocarpan chemical structure. It consists of a 1-benzofuran moiety (dotted blue circle) fused to a 2 H -chromene moiety (dotted green circle). The systematic name for it is 6 H -[1]benzofuro[3,2-c]chromene. The new numbering of the resulting moiety is shown with red numbers.
Medicarpin chemical structure
Phaseolin – a prenylated pterocarpan – chemical structure
Glyceollin III – a prenylated pterocarpan – chemical structure